The universe gives up its deepest secret

It is the invisible material that makes up most of the cosmos. Now, scientists have created the first image of dark matter

One of the greatest mysteries of the universe is about to be unravelled with the first detailed, three-dimensional map of dark matter - the invisible material that makes up most of the cosmos.

Astronomers announced yesterday that they have achieved the apparently impossible task of creating a picture of something that has defied every attempt to detect it since its existence was first postulated in 1933.

Scientists have known for many years that there is more to the universe than can be seen or detected through their telescopes but it is only now that they have been able to capture the first significant 3D-image of this otherwise invisible material.

Unlike the ordinary matter of the planets, stars and galaxies, which can be seen through telescopes or detected by scientific instruments, nobody has seen dark matter or knows what it is made of, though calculations suggest that it is at least six times bigger than the rest of the visible universe combined.

A team of 70 astronomers from Europe, America and Japan used the Hubble space telescope to build up a picture of dark matter in a vast region of space where some of the galaxies date back to half the age of the universe - nearly 7 billion years.

They used a phenomenon known as gravitational lensing, first predicted by Albert Einstein, to investigate an area of the sky nine times the size of a full moon. Gravitational lensing occurs when light from distant galaxies is bent by the gravitational influence of any matter that it passes on its journey through space.

The scientists were able to exploit the technique by collecting the distorted light from half a million faraway galaxies to reconstruct some of the missing mass of the universe which is otherwise invisible to conventional telescopes.

"We have, for the first time, mapped the large-scale distribution of dark matter in the universe," said Richard Massey of the California Institute of Technology in Pasadena, one of the lead scientists in the team. "Dark matter is a mysterious and invisible form of matter, about which we know very little, yet it dominates the mass of the universe."

One of the most important discoveries to emerge from the study is that dark matter appears to form an invisible scaffold or skeleton around which the visible universe has formed.

Although cosmologists have theorised that this would be the case, the findings are dramatic proof that their calculations are correct and that, without dark matter, the known universe that we can see would not be able to exist.

"A filamentary web of dark matter is threaded through the entire universe, and acts as scaffolding within which the ordinary matter - including stars, galaxies and planets - can later be built," Dr Massey said. "The most surprising aspect of our map is how unsurprising it is. Overall, we seem to understand really well what happens during the formation of structure and the evolution of the universe," he said.

The three-dimensional map of dark matter was built up by taking slices through different regions of space much like a medical CT scanner build a 3-D image of the body by taking different X-ray "slices" in two dimensions.

Data from the Hubble telescope was supplemented by measurements from telescopes on the ground, such as the Very Large Telescope of the European Southern Observatory in Chile and the Japanese Subaru telescope in Hawaii.

Details of the dark matter map were released yesterday at the annual meeting of the American Astronomical Society in Seattle and published online by the journal Nature. The map stretches half way back to the beginning of the universe and shows that dark matter has formed into "clumps" as it collapsed under gravity. Other matter then grouped around these clumps to form the visible stars, galaxies and planets.

"The 3-D information is vital to studying the evolution of the structures over cosmic time," said Jason Rhodes of the Jet Propulsion Laboratory in Pasadena.

Astronomers have compared the task of detecting dark matter to the difficulty of photographing a city at night from the air when only street lights are visible.

Scientists said the new images were equivalent to seeing a city, its suburbs and country roads in daylight for the first time. Major arteries and intersections become evident and a variety of neighbourhoods are revealed.

"Now that we have begun to map out where dark matter is, the next challenge is to determine what it is, and specifically its relationship to normal matter," Dr Massey said. "We have answered the first question about where the dark matter it, but the ultimate goal will be to determine what it is."

Various experiments on Earth are under way to try to find out what dark matter is made of. One theory is that it is composed of mysterious sub-atomic particles that are difficult to detect because they do not interact with ordinary matter and so cannot be picked up and identified by conventional scientific instruments. Comparing the maps of visible matter and dark matter have already pointed to anomalies that could prove critical to the understanding of what constitutes dark matter.

Start your day with The Independent, sign up for daily news emails
Voices
Homeless Veterans charity auction: Cook with Angela Hartnett and Neil Borthwick at Merchants Tavern
charity appealTime is running out to secure your favourite lot as our auction closes at 2pm tomorrow
Arts and Entertainment
J Jefferson Farjeon at home in 1953
booksBooksellers say readers are turning away from modern thrillers and back to golden age of crime writing
Sport
Amir Khan is engaged in a broader battle than attempting to win a fight with Floyd Mayweather
boxing Exclusive: Amir Khan reveals plans to travel to Pakistan
News
Stacey Dooley was the only woman to be nominated in last month’s Grierson awards
mediaClare Balding and Davina McCall among those overlooked for Grierson awards
PROMOTED VIDEO
Voices
Joseph Kynaston Reeves arguing with Russell Brand outside the RBS’s London offices on Friday
voicesDJ Taylor: The great tradition of St Paul and Zola reached its nadir with a worker's rant to Russell Brand
News
Twitchers see things differently, depending on their gender
scienceNew study shows that birdwatching men have a lot in common with their feathered friends...
News
i100
Arts and Entertainment
Caroline Flack became the tenth winner of Strictly Come Dancing
tvReview: 'Absolutely phenomenal' Xtra Factor presenter wins Strictly Come Dancing final
Life and Style
A still from the 1939 film version of Margaret Mitchell's 'Gone with the Wind'
life
News
Xander van der Burgt, at the Royal Botanic Gardens, Kew
scienceA Kew Gardens botanist has found 25 new large tree species - and he's sure there are more out there
Arts and Entertainment
British actor Idris Elba is also a DJ and rapper who played Ibiza last summer
film
ebooks
ebooksA year of political gossip, levity and intrigue from the sharpest pen in Westminster
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Finance Director

£65000 - £80000 per annum: Recruitment Genius: Finance Director required to jo...

Recruitment Genius: Medico-Legal Assistant

£15000 - £25000 per annum: Recruitment Genius: This is a unique opportunity fo...

Ashdown Group: (PHP / Python) - Global Media firm

£50000 per annum + 26 days holiday,pension: Ashdown Group: A highly successful...

The Jenrick Group: Quality Inspector

£27000 per annum + pension + holidays: The Jenrick Group: A Quality Technician...

Day In a Page

The week Hollywood got scared and had to grow up a bit

The week Hollywood got scared and had to grow up a bit

Sony suffered a chorus of disapproval after it withdrew 'The Interview', but it's not too late for it to take a stand, says Joan Smith
From Widow Twankey to Mother Goose, how do the men who play panto dames get themselves ready for the performance of a lifetime?

Panto dames: before and after

From Widow Twankey to Mother Goose, how do the men who play panto dames get themselves ready for the performance of a lifetime?
Thirties murder mystery novel is surprise runaway Christmas hit

Thirties murder mystery novel is surprise runaway Christmas hit

Booksellers say readers are turning away from dark modern thrillers and back to the golden age of crime writing
Anne-Marie Huby: 'Charities deserve the best,' says founder of JustGiving

Anne-Marie Huby: 'Charities deserve the best'

Ten million of us have used the JustGiving website to donate to good causes. Its co-founder says that being dynamic is as important as being kind
The botanist who hunts for giant trees at Kew Gardens

The man who hunts giants

A Kew Gardens botanist has found 25 new large tree species - and he's sure there are more out there
The 12 ways of Christmas: Spare a thought for those who will be working to keep others safe during the festive season

The 12 ways of Christmas

We speak to a dozen people who will be working to keep others safe, happy and healthy over the holidays
Birdwatching men have a lot in common with their feathered friends, new study shows

The male exhibits strange behaviour

A new study shows that birdwatching men have a lot in common with their feathered friends...
Diaries of Evelyn Waugh, Virginia Woolf and Noël Coward reveal how they coped with the December blues

Famous diaries: Christmas week in history

Noël Coward parties into the night, Alan Clark bemoans the cost of servants, Evelyn Waugh ponders his drinking…
From noble to narky, the fall of the open letter

From noble to narky, the fall of the open letter

The great tradition of St Paul and Zola reached its nadir with a hungry worker's rant to Russell Brand, says DJ Taylor
A Christmas ghost story by Alison Moore: A prodigal daughter has a breakthrough

A Christmas ghost story by Alison Moore

The story was published earlier this month in 'Poor Souls' Light: Seven Curious Tales'
Marian Keyes: The author on her pre-approved Christmas, true love's parking implications and living in the moment

Marian Keyes

The author on her pre-approved Christmas, true love's parking implications and living in the moment
Bill Granger recipes: Our chef creates an Italian-inspired fish feast for Christmas Eve

Bill Granger's Christmas Eve fish feast

Bill's Italian friends introduced him to the Roman Catholic custom of a lavish fish supper on Christmas Eve. Here, he gives the tradition his own spin…
Liverpool vs Arsenal: Brendan Rodgers is fighting for his reputation

Rodgers fights for his reputation

Liverpool manager tries to stay on his feet despite waves of criticism
Amir Khan: 'The Taliban can threaten me but I must speak out... innocent kids, killed over nothing. It’s sick in the mind'

Amir Khan attacks the Taliban

'They can threaten me but I must speak out... innocent kids, killed over nothing. It’s sick in the mind'
Michael Calvin: Sepp Blatter is my man of the year in sport. Bring on 2015, quick

Michael Calvin's Last Word

Sepp Blatter is my man of the year in sport. Bring on 2015, quick